Formation mechanism of thermosensitive chitosan hydrogels containing uridine 5’-monophosphate disodium salt

In this study, the gelation mechanisms of two types of thermosensitive chitosan hydrogels containing uridine 5’-monophosphate disodium salt (UMP) as a sol-gel transition agent were investigated. These systems were prepared from chitosan lactate and chitosan chloride solutions and are characterised by the ability to transition from sol to gel at both low and high temperatures. The formation mechanisms of the above hydrogels were developed based on our previous studies and the analysis of FTIR spectra of the chitosan systems at 4°C and 37°C without and with the addition of uridine 5’-monophosphate disodium salt. It has been demonstrated that the sol-gel transition of chitosan colloids is a complex, multi-step process resulting from the coexistence of multiple interactions (electrostatic interactions, hydrogen bonds and hydrophobic interactions) that determine the final properties of the hydrogels.